Selective system



July 28, 1936. 'r. A. RICH SELECTIVE SYSTEM 7 Filed Jan. 20, 1955 F'igl.

Invent-0v Theodore APich, W W

His Attorney.

Patented July 28, 1936 PATENT OFFICE SELECTIVE SYSTEM Theodore A. Rich, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application January 20, 1933, Serial No. 652,681

Claims.

My invention relates to selective remote control systems and it has forone of its objects, to provide means whereby a plurality of remote devices may be operated in a reliable and satisfac- 5 tory manner and by means which may be more economically constructed than has heretofore been possible.

My invention has particular application in connection with the remote control of streetlamps and domestic water-heaters over the lines of the power distribution'system from which these instrumentalities are energized. In these applications the control is effected by carrier current transmitted from a control station over the power line to actuate selectors arranged in the base of the street lamp, or at the location. of the water heaters. The domestic Water heaters are controlled from a central point by the power com pany which supplies the power in order that the Particularly, in the application to the control of domestic water heaters, it is further desirable not only that the system be capable of selectively turning the water heaters on and off in response 30 to selective operations at the central station, but

also that it be capable of turning all of the water. heaters off non-selectively in response to some simple operation atthe central station which can be easily and hastily performed. This feature is 1 desirable in order to permit the entire water heater load to be-quickly removed from the system.- This is necessary at times-when the load indicators at the central station indicate that the power load is approaching the value atv which the 40 line circuit breakersopen, thereby to. disconnect the generating system from the line and producing a general failure of power. Were the circuit breakers allowed toopen, some time would be required to put the generating station back on the 45 line, whereas the power-companies are oftensubjected to heavy penalties for each minute of failure of power. The opening of the circuit breakers can in many instances be avoided by disconnecting a portion of the load to which-the 0011- 50 tinuous supply of power is notimportant, suchas domestic water heaters. Accordingly, it is an object of my invention to provide a system capable not only of selectively turning theloadde vice on and off but alsocapable of non-selective: 55 operation to turn all of the'devices 01f. r

water-heater may be cut 011" during periods of The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention itself, however, both as to its organization and method. of operation, together with further ob- 5 jects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing in which Fig. 1 represents the receiving selector system, Fig. 2 illustrates the transmitting 10 means employedtherewith, and Fig. 3 is a detail view of a portion of the receiver of Fig. 1.

Referring first to'Fig. 2, I have indicated at therein a power distribution system having a feeder 2 extending to a generating station 3 15 through the secondary winding of a high frequency transformer 4. The primary winding of this transformer is arranged to be connected through the contacts of a switch 5 to a high frequency alternator 6. This alternator may be one 20 adapted to generate any desired frequency capable-of being practically superposed upon the currents of the power line. A frequency of 720 cycles-is commonly employed. The operating solenoid l of the switch 5 is arranged to be energized from a battery 8 through a switch 9. The switch 5,is ordinarily maintained in its closed position during periods when the alternator 6 is operated. The high frequency carrier is controlled by a relay l 0 having contacts in series with the alternator. The operating winding of this relay is controlled by contacts I l and a relay l2. Contacts I areithe ordinary keying contacts of a keying device l3 such as an ordinary telephone dial. This device has a pair of off-normal contacts conventionally indicated at M, which are arranged to close whenever the dial [3 is oper-- ated'in a clockwise direction from its normal position. These contacts control the energization of the relay I2. The relay l 2 is provided with apair 40 of contacts and armature l 5 which close immediately upon energization of the winding. It is also provided with a second armature l6 having a time delay device I! associated therewith, whereby its actuation is delayed for a predetermined interval such, for example, as 30 seconds.

When the operator desires to operate a remote device as, for example, to turn on a remote water heater, he operates the dial l3 in a clockwise direction to a desired position. Upon initial actuation of the dial l3, contacts I4 immediately close thereby energizing the windings ofrelays l0 and I2. Relay I!) immediately closes and supplies carrier current to the feeder. Contacts l5 of relay 12 also immediately close and complete M gized or deenergized.

a holding circuit for 'this relay through the winding and contacts l6 thereof. This circuit is maintained for the above-mentioned interval determined by delay device I1. When the operator releases his dial, contacts II are opened a number of times dependent upon the position to which the dial has been operated after which the dial returns to its-normal position opening; contacts 14. The opening of contacts, I I causes the carrier to be interrupted to produce a predetermined number of short impulses. The interval 5,

left end of the detent 58 is bowed, the bowed pordetermined by the time delay device I1, however,

is substantially longer than the interval 'requi'red' for the dial l3 to return tojits initial position with the result that following; the-transmission;

plill fes a m ed. is 6. h 1 i mq device. which is toflbe'actuated and the'long impulse isemployed to actuate'the selected remote deg Injc ase it be'desired' topperate all of" the "re- 30 mote devices as, for examplein ithe'watr heater application referred to, to deenergiz'e all-the waterheaters, a switch l 8 may be closed. 1 This switch causes the closing of relay 1 0 and thereby causes carrier current to be supplied-to the-line continu 5 ceiving mechanism provided in acc rdance: with my invention isadapted to respond -to such acarrier impulse to operate the remote devices; I

"Referring" now to Fig. 1, 1 have shown t'herein' wsa'i acr device '1 s whichisindicated as a lamp but I which";InayQcomprise any desired device -to';becontrolled; *This device is" energized through a H circuit extending 'from1the lower. terminal -of the' power linefthrough the load device, cc'mtaots" 5 22 I and 22, bimetallic strip 23," and: conductor 24, n

back totheopposite side of 'the 'power line-*20'. Contact 22 is carried onthe end of bimetallic strip 23 which when heated, by passing current: through; the winding- 25 thereon defiects'away ifronr'the contact 2| sufficient'ly 'to permit a second bimetallic" strip 26 to fall behind -it'; thereby to prevent its return to he 'position shown in the drawing; The bimetallic strip 26 is also provided? with ajheating winding "21" and is adaptedwheni :mate to] deflect upward :frpm behind the strip 23 thereby topermit the strip "23 to return to its 1 initial position. by selectively "energizing the windings 25 and 2T, he load" [8 may be ener One"t erminal ofr'e'aoh "of the's'e'windings :isconnested to the respective bimetallic strip which in turn; is connected throug'hconductor} 24' to the-=- upperside of the power linefl-The opposite ter-; minal of these windingsis connected respectively Upon rotation of the shaft 31 and disk 36 the actuated by means'of a ratchet 39 and pawl 40.

The pawl 40 is actuated by theiarmatu're 4| of the 'electromagnet 3|. This armatureis pivoted 1 at the point 42 and is biased by means of a spring 43. away fr-om the magnet and, thereby retains the pawl .40 inits lefti hand-position. The pawl 40' is forced against the teeth of the ratchet by means of a spring member 44 and detent 58. The

tionbeing" pivoted upon the end of spring 44v which is mounted on an arm 41 of the frame of the apparatus; The left end of the bow rests against the'iteethiof' the ratchet, whereas the jof thespring 44. The contact 45 when in the positionshown in the drawing makes engagement 20 with the insulated contact 46. When the pawl 49' is actuated to the" right, however; by 'energization of the: magnet 3!, the contact 45'is retained in its closed position-until the pawl 40 is forced upward under influence of spring '44 against the 25;

next *tooth of the ratchet; 'When this'occursthe detent 58 is rotated about its pivot in a counterline 2'0 through the winding 3|; conductor 48,}

shaft '31, ratchet 39, contacts 45 and 46', and

resistance '49,-"to the opposite side of the powered? line; "Thus, whenever the contact 45 is in the n position shown in the arm ng; current flows in-- thef above t'rac'ed circuit; This current is in- T suiiicient to'ener'gize themagnet3|, The resis" tance "49-,- however; i's theheatin'g unit ofa biinfliienceof heat froni r'lesistance 49 short circuits J that-resistancer- 'Suflic-ient current then flows in the' magnet 3l'to causeoperation of the selector; j 5 V The magnet 3| attractsits' armature; thereby causing-the pawl :40 to bemoved to the'right until it isforced'upward under the influence of biasingspring 44 against the nextiad'jacent tooth of V K theselector; When' this occurs, contact 45 leaves engagement with ct intactf' lli andinterrupts' the circuit of the magnet. Spring-43 then pulls the] armature 4| away from the magnet and 'actu if ates the'pawlw toward the left; thereby operat-" ing the ratchetthrough the spaceof one tooth. 7 7

This'operation repeats itself until a member 5| of the jdiskn36 engages the projection 52. This latter. projqtionjgis a portion "of a member 53 I which is supported at its upper end iro'm'the frameof ;the apparatus-beinginsulated therefrom and-:has a lower arm 54 which is adapted i tobe operated beneath detent 58 when the latter s is 'in'iits upper position. Thatis engagement of member 5| withprojection 52 forces the arm 54 underneath detent 58, thereby toprevent contact Y v i .7 i 40- metallic strip 50 which when deflected under the '75 a shaft31""andcarrying -a contact member as,

to contactjsf28 and a selector fwhereby'; they areselectively connected to the o l l bsite side of the power line. 1

deenergization of the magnet 3|. This in turn' permanently fdeenergizes the magnet *3! and causSthe'di'sk 39 to be maintained in the posi tion in which the member 5| engages; the contact 52; p ra us,- L. V I1 i Y a Now let us suppose that "the operator at the central lstation desiresto disconnect the load l9 from thep'ower line. I -I e ,-will=operatehis dial 4 I? to th positioncorrespondingto the desired 5 V (actor 31], i sfjoperatedby a -ma'gnet 31" which in "turn is energized'jby a receiving'relay' 7 j 32'lwhich s connected in the output of a carrier currentir iver 3 3, receiver is adaptedto" respond tof carrier current received? in a tuned circnit connecte'd acrossthe power line;

' Th selector -3 mp s-a disk-'36 fixed'upon from engaging with contact '46 upon the next I 1 This is :the normal position of the-7 1:

'defiect away from the contact 2|.

2,04egs19 operation, thereby supplying to the line 20 anumber of short carrier impulses followed by a long impulse. Each of these impulses causes operation of the relay 32 which in turn energizes the magnet 3| through an obvious circuit in accordance with the impulses. The selector is therefore actuated by its ratchet and pawl mechanism through a number of steps corresponding to the number of short impulses re ceived. The number of short impulses will be such that the selector is so operated that contact 38 engages contact 28, thereby completing a circuit for the subsequent long impulse. This circuit extends from the lower side of the power line through the contacts of relay 32, conductor 48, shaft 3], disk 36, contacts 38 and 28, winding 25, bim'etallic'strip 23, and conductor 24, to the opposite side of the power line. The long impulse is of such duration that the bimetallic strip 23 will be suificiently heated to cause it to It is then retained in its deflected position by strip 26 falling behind it. During the long impulse the magnet 3I is maintained continuously energized.

' The pawl 46 is therefore in its right-hand position and the contact 45 in its open position. Resistance '49 is therefore cold. Upon termination of the long impulse, the magnet 3| becomes deenergized and. the contact 45 is at once operated into engagement with contact 46, thereby completing the above-traced circuit for resistance 49. After a short interval, strip 50 short circuits resistance 49 and thereby causes the selector to be actuated to its normal position, as previously described.

Now, if the operator desires to energize the load l9, he will operate the dial l3 to a difierent position thereby transmitting a difierent number of short impulses to actuate the contact 38 into engagement with contact 29, whereupon the heating unit 21 is energized during the period of the subsequent long impulse. This in turn causes the bimetallic strip 26 to deflect upward sufiiciently to release the strip 23, which in turn again closes the load circuit. After termination of the long impulse the selector again returns to its normal position.

It will now be understood that a selector of the type described is employed in connection with each of the water heaters toi. be controlled. These selectors may be arranged to turn all the water heaters on in response to a particular code combination of impulses and to turn them all off in response to a diiferent code combination of impulses, or the difierent selectors may be arranged to efi'ect these operations in response to codes diiferent from those to which other selectors respond, as desired. If desired, additional pairs of contacts 28, 29 may be provided on any selector whereby it may be responsive to different codes to control additional load devices. It is desired, however, that all of the selectors be adapted to respond to a common signal transmitted from the central station to turn their respective water heaters off. For this purpose, a circuit is provided which extends from the lower side of the power line 20 through the contacts of relay 32, conductor 48, shaft 37, disk 36, when in its normal position, members 5| and 52, conductor 55, contact 28, heating winding 25, bimetallic strip 23, and conductor 24, to the other sid of the line. This circuit is completed whenever relay 32 is energized and selector 36 is in its normal position. Thus, if the operator at the central station holds the switch l8 in its closed position thereby sending out a long impulse, the unit is energized for a sufficient period to cause the load I 9 to be deenergized.

The particular mechanical construction and arrangement of the pawl 40, ratchet 39, and de- 5 tent 58 is of importance in the operation of the selector described, for the reason that it assures positive operation of the selector and at the same time avoids overrunning of the ratchet. It will be noticed that the pawl is operated to the right 16 and left in substantially the plane of the pawl and that the contact 45 is held in engagement with contact 46 which is supported by, but in sulated from, the supporting arm 4'! until the H pawl in its movement to the right slips off the 16 edge of the ratchet tooth against which it is pressed by the detent 58 under the bias of spring 44. Contacts 45 and 46 then separate, deenergizing magnet 3| which allows spring 43 to return M the pawl to its extreme left-hand position. This 20- left-hand movement of the pawl is limited by the edge 51 of the pawl engaging shaft 31. The ratchet is thereby rotated clockwise an amount equal to one tooth, further rotation being prevented by the extension 56 of the ratchet engag- 25* ing the shaft. Just prior to the ratchet reaching this position the detent 58 drops to the root of the next tooth, and in so doing the detent rotates clockwise to close the contacts 45, 46 to reenergize magnet 3|.

While I have shown a particular embodiment of my invention, it will of course be understood that I do not wish to be limited thereto since many modifications may be made both in the circuit arrangement and the instrumentalities employed. I, of course, contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. The combination, in a selector system, a control device having a plurality of actuating members, a selector having a normal position and a plurality of other positions, said actuating members being connected respectively to said other positions of said selector, means responsive to coded impulses to operate said selector from said normal position to any of said other positions, means to energize the selected actuating member through said selector in the selected other position, and means to energize a predetermined one of said actuating members through said selector when said selector is in said normal position.

2. The combination, in a remote control system, a plurality of devices to be actuated, a receiving relay, a selector having a normal position and a plurality of other positions corresponding to said devices to be actuated, means responsive to. said receiving relay to operate said selector to any one of said other positions, means responsive to said receiving relay to energize the selected device when said selector is in the position corresponding thereto, means responsive to said receiving relay to energize said one of said devices when said selector is in said normal position, and means to prevent actuation of said one of said devices in response to actuation of said receiving relay to operate said selector to one of said other positions.

3. The combination, in a remote control system, a plurality of devices to be actuated, a receiving relay, a selector having a normal position and a plurality of other positions corresponding 7 to saiddevicesto be actuated, meansresponsive i to saidreceiving relay to operate said selector toany one of said other positions, means responsive to saidreceivingcrelay to energize the selj lected device when said'selector is in the'position corresponding thereto, and means responsivelto said receiving relay to'energize one of said devices: when said selector. is in said normal position, said last means being ineffective to ac- 10.:tuate said one device upon operation of saidsee lector to any of said other positions.

4.;In combination, a load contact, means to operate said contact-to closed position, means to operate said contact to open position, means oplli erable from a control point to transmiteither a long impulse or combinations of impulses, each combination comprising a plurality of short impulses followed'by a lon-gimpulse, means responsive to said short impulses to; select a predeter- 20: ;mined one of said operatingimeans, meansresponsive to the long impulse following said short l impulses to actuate theoperating means selected by said last means, and means responsive to the first-mentioned long impulse to'operateone of 25 .g;said operating means, whereby said load contact may be operated to one position in response to 7 said first-mentioned longiimpulse, and maybe selectively operated to either 1 position fin-response to said combination of;impulses.- 5. The combination in a remote control system, .a control member arranged to be operated betweentwo positions, a plurality'iof devices to 5 'fromoneposition to its second position, means automatically operable after said long impulsezo V is terminated to actuate said selector to said.

' normal position and means for energizing one of said devices when said selector isin saidnormal; position thereby to operate said control member to a predetermined. oneof its two operating.-posi-. 25

THEODORE A RICll-l. 1 

